Messages

1

General Mach Discussion / Re: Rack & Pinion step setup

« on: March 20, 2012, 12:30:48 PM »

Here is the video recorded today.

Settings:

steps per mm: 57,7
velocity: 15000 mm per min
accelaration: 550 mm per sec

I think I will adjust correct step count only with mach3 steps per unit calibration. I can't see other options.
But I would like to know where is the problem with my calculation or drives or steppers. In that case I will be able to setup everything correctly.

2

General Mach Discussion / Re: Rack & Pinion step setup

« on: March 20, 2012, 12:22:57 PM »

Actually I was setup'ed 1/8 stepping (settings from pic above: OFF / OFF / ON / ON). I left the steps per mm setting about 120 (as my calculations was with 1/16 stepping). And it was very close to real distance travel  (moved 100 mm and only 2mm's  was traveled more than needed).

So I'm really confused.

3

General Mach Discussion / Re: Rack & Pinion step setup

« on: March 20, 2012, 12:02:03 PM »

Ok I see you had that in your post, I sometimes dont read properly when at work

So then it will be twice what I said and I see you have it correct as well in your calcs. Now you say it works out at only approx 57 when you use the Set Steps utility and measure so I can only assume you have a 0.9 degree stepper motor rather than the normal 1.8 degree.
Hood.

In motor spec's says that motors are 1.8 degree:
http://www.zappautomation.co.uk/sy60sth883008-nema-stepper-motor-p-24.html?cPath=9_159_42
strange.
is the 0.9 degree motors worse than 1.8 ?

4

General Mach Discussion / Re: Rack & Pinion step setup

« on: March 20, 2012, 11:43:37 AM »

Thank you for reply.

The steping is set to 16 mircrosteps



my setting is ON / OFF / ON / ON

5

General Mach Discussion / Rack & Pinion step setup

« on: March 20, 2012, 10:20:27 AM »

Hello everybody.

I'm using rack & pinion drive system.

I need help from you guys to calculate step per mm correctly  .

I saw  calculation example in INCH. I used same calculation calculating steps per mm. But I getting wrong step count.
My calculation:

circle pitch 25.4mm (1")
25.4 * pi = 79.796453
79.796453 / 3 = 26.598817 (reduction)
26.598817 / 200 = 0.132994 (mm per step)
1 /  0.132994 = 7.51913 (steps per mm)
 7.51913 * 16 = 120.30609 (16x microstepping)

I used mach 3 steps per unit calibration, and come out with pretty accurate results - ~ 57.6 steps per mm.
So I'm wondering where I miscalculated ? I need to calculate it accurately

Thank you guys for help !